TeamViewer

Perfect software for sweating sessions/coaching if you guys are interested.

Make SURE you trust the guy you're doing this with and that you obv don't reveal any personal information like passwords/address etc by accident.

Anyways the way it works is that the player who wants to actually play sets a password into the program, tells it to the guy who wants to watch, and then the program lets the watcher see the player's desktop. Should work great in conjunction with a messenger program.

There are also file transfer capabilities among other features that I admittedly don't understand

teamviewer.com